This application claims the priority of German patent document 101 30 441.1, filed Aug. 10, 2001, the disclosure of which is expressly incorporated by reference herein, and is a Continuation-In-Part of U.S. patent application Ser. No. 10/214,729, filed Aug. 9, 2002 now abandoned.
The invention relates to a method for repairing solar a cell panel.
Heretofore, the repair of a solar cell panel with one or more defective solar cells, solar cell modules or solar cell strings has conventionally been accomplished by the complete removal and replacement of the defective cell or cells (sometimes referred to as a solar cell array), as described, for example, in German Patent Document DE 1 927 387. Moreover, German Patent Document DE 2 113 410 describes a repair-friendly arrangement of solar cells, in which a defective cell can easily be removed from a module or string of solar cells. Furthermore, German Patent Document DE 195 39 699 C2 describes the utilization of defective solar modules of a laminated construction, in which the solar cells are delaminated and the solar cell module is disassembled into its components. This state of the art in each case requires a relatively high-expenditure intrusion into the solar cell panel or into the solar cells, such that the resulting repaired solar cell panels may suffer damage.
The known repair methods according to the state of the art may, for example, require the following steps: The cover glass over the one or more solar cells is removed at the welding islands of the top xe2x80x9cn-connectorsxe2x80x9d of the solar cells to permit them to be separated and carefully bent up, exposing connection webs directly behind the welds. Subsequently, the defective one or more solar cells is or are removed from the solar cell panel, the xe2x80x9cp-connectorxe2x80x9d being retained on the panel. Then, one or more solar cells having a special repair connector are inserted into the repair site and the projecting n- and p-connectors are welded to the adjacent solar cells. Such separation of the defective solar cell or cells, which also requires high expenditures, may result in damage to the panel structure as well as to adjoining solar cells. Moreover, the use of such repaired solar cell panels with possible damage is problematic, particularly for applications of solar panels which, after being placed in service, allow no simple further repair of solar cells, as, for example, for aerospace applications. In addition, special repair connectors are required for repaired solar cell panels according to the state of the art and a new insulation foil must be provided.
It is an object of the present invention to provide a safe and effective method for repairing solar cell panels with defective solar cells, which does not have the disadvantages of the state of the art.
This and other objects and advantages are achieved by the method according to the invention, which is based on the proposition that one or more defective solar cells, or solar cell strings, solar cell modules or another defined group of defective solar cells, continue to be physically part of the solar cell panel, and that these defective solar cells are not removed from the panel structure. (In this case, the term xe2x80x9csolar cellsxe2x80x9d includes a solar cell xe2x80x9cassemblyxe2x80x9d (SCAs) consisting of the solar cell, the solar cell connector and cover glass.)
According to the invention, one or more replacement solar cellsxe2x80x94also in the form of solar cell assemblies (SCAs)xe2x80x94are glued onto the defective solar cell or cells and are electrically integrated in the panel by means of the existing cut-open connectors. Therefore, either one defective solar cell may exist in the panel onto which the one or more intact replacement solar cells are glued, or several defective solar cells may be present which are directly adjoining, grouped or spatially separated (particularly in the form of entire solar cell strings or solar cell modules), onto which one or more intact replacement solar cells are glued. In cases in which complete defective solar cell strings, solar cell modules or other defined groups of solar cells are present, complete replacement solar cell strings or replacement solar cell modules can correspondingly be glued thereon.
The invention achieves a saving of components and materials. Another important advantage is a reduction of the repair time that is required for producing such repaired solar cell panels, because the time consuming separation of the defective solar cells is eliminated, only the connectors needing to be exposed.
A further embodiment of the invention provides that the one or more replacement solar cells are provided with standard-type n-connectors and p-connectors which are electrically connected (particularly welded) to cut-open connectors of one or more adjacent intact solar cells. The replacement solar cells may be glued on by means of a silicone glue.
Specifically, the present invention can be used in the case of solar cell panels that are constructed for aerospace applications (for example, solar cell panels for satellites or other spacecraft). In every case, the use of repaired solar cell panels will be more cost-effective than, for example, a complete elimination of solar cell panels because of some defective solar cells.
In order to apply the one or more replacement solar cells to the defective solar cell or the cells as described above, a protective cover foil can be used. For this purpose, the solar cell panel is covered by a Kapton foil with a window cut out adjacent the defective solar cell or cells. The window edges of the foil are preferably glued by means of adhesive tape, onto the adjacent intact solar cells in such a manner that the latter solar cells are protected by the foil during the repair operation. This process step is therefore advisable when special protection of the adjacent solar cells must be ensured.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.